Plugging apparatus for well tubing



Jan. 19, 1960 L. L. GAGE 2,921,631

PLUGGING APPARATUS FOR WELL TUBING Filed NOV. 15, 1957 I INVENTOR. Lonme L. Gage United States Patent A 2,921,631 PLUGGING APPARATUS FOR WELL'TUBING Y Lonnie L. Gage, Duncan, Okla.

Application November 15, 1957, Serial No. 696,798 3 Claims. (Cl. 166-492) bing tool prior'to the removal of the tubing from the well. However, particularly in the case of wells which are producing their well fluid through the tubing, the fluid tends to flow upwardly or come up through the tubing during the pulling thereof from the well bore. The oil products flowing upwardly through the tubing spill out onto the working area around the well and create a hazard for the servicing personnel. Not only must the personnel stand in the fiuidwhile Working on the well, but also the well fluid is normally highly inflammable and may accidentally be ignited upon contact with a hot spark. It is sometimes necessary to shut down a well, or kill the well in order to prevent the well fluid from coming up through the tubing. This is usually only a last resort operation, though, since it is often very diflicult or impossible to start the How of the fluid from the well after the killing operation.

well. The novel plugging apparatus comprises a seating nipple for receiving a seal member which is adapted to be disposed on the swabbing tool prior to the swabbing of the inner periphery of the tubing. The nipple may be inserted into the tubing as the swab is lowered therein.

The seal member is adapted to be securely lodged within the seating portion of the seating nipple as the swab is lowered suflicieutly within the well tubing. The swab may then be raised within the tubing for a disengagement with the seal member. The swabbing operation may be continued in any well known manner as is normally utilized. The seal member efliciently seals the interior of the tubing in order to preclude the flow of fluid therethrough. Thus, the tubing may be serviced or removed from the well without the undesirable upward flow of the well fluid therethrough. It will be apparent that the novel plugging apparatus permits the pulling of the well tubing without disturbing or endangering any future flow of the fluid from the well bore.

' i It is an important object of this invention to provide a 2,921,631 Patented Jan. 19, 1960 be readily disposed therein when it is desired to service or pull the tubing string from the Well bore.

Still another object of this invention is to provide a plugging apparatus for a well tubing string which in no manner hinders or interferes with the normal utilization of the tubing string during the production of fluid from the well bore.

A further object of this invention is to provide a novel plugging apparatus for well tubing which is simple and efiicient in operation and economical and durable in construction.

Other objects and advantages of the invention will be evident from the following detailed description, read in conjunction with the accompanying drawing, which illustrate my invention.

In the drawing the single figure is a vertical sectional view of the novel plugging apparatus.

Referring to the drawing in detail, reference character 10 refers in general to a plugging apparatus comprising an outs-r tubular housing member or seating nipple 12 and an inner seal member 14. The housing 12 is suitably threaded at the uppermost end 16 thereof for receiving a well tubing section (not shown). The lowermost end 18 thereof may be suitably internally threaded, as shown in the drawings, for receiving a dual completion packer unit 19, such as disclosed in my co'pending application entitled Dual Completion Packer Tool, filed on even date herewith, if desired. It will be apparent that the end 18 of the housing or seating nipple 12 may be suitably threaded for receiving a well tubing section, if desired, in order to interpose the plugging apparatus 10 at any de sired position within the tubing string.

The inner bore 20 is preferably substantially of the same diameter as the well tubing string with which the plugging apparatus 10 is to be utilized. The lower portion 22 of the bore 20 is enlarged in order to provide a circumferential shoulder 24. The inner periphery of the housing 12 is preferably tapered inwardly at 26 adjacent the shoulder 24 for a purpose as will be hereinafter set forth.

The sealing member 14 is of a substantially cylindrical configuration and is preferably constructed from a suitable flexible material, such as rubber, or the like, but not limited thereto. A centrally disposed threaded bore 28 is provided in the upper end 30 of the sealing member 14, as viewed in the drawings. The bore 28 is adapted to receive the lower end of a suitable swabbing tool (not shown) for a purpose as will be hereinafter set forth. An outwardly and upwardly extending circumferentialflange 32 is provided at the upper end 30 of the seal 14. A similar flange 34 extends outwardly and downwardly from the lower end 36 thereof. When the seal member 14 is in a sealing position within the housing or seating nipple 12, as shown in the drawing, the upper flange 32 bears against the shoulder 24 for precluding upward movement Operation dual completion unit 19. When it is desired to stop the the seal 14.

3 upward flow of the well fluid through the tubing for any reason, such as for pulling the tubing from the well, the sealing member 14 may be threadedly secured to the lowermost end of a suitable swabbing tool (not shown) through connection with the threaded bore 28. The swabbing tool may then be lowered orinserted within the tubing in any suitable manner (not shown) with the sealing member 14 secured thereto. The outwardly extending flanges 34 and 32 tend to wipe theinner periphery of the tubing string as the seal member 14 moves downwardly therethrough, thereby facilitating the action of the swabbing tool. When the swabbing tool has been sufficiently lowered within the tubing string, the lowermost flange 34 of the seal 14 is moved adjacent the'inwardly tapering surface 26. The taper 26 functions to urge the flexible flange 34 radially inward whereby the seal member 14 will enter the enlarged bore portion 22 of the housing 12. A further downward movement of the swabbing tool will move the uppermost flange 32 adjacent the tapered portion 25 for facilitating disposition thereof within the enlarged portion 22. The downward movement of the seal member 14 within the enlarged portion 22 will be limited by contact between the lower flange 34 and the dual completion packer unit 19.

When the seal member 14 has then been disposed within the enlarged portion 22, the swabbing tool may be raised within the tubing string for a disengagement with As hereinbefore set forth, the upward movement of the seal member 14 within the enlarged portion 22 is limited by the contact between the upper flange 32 and the shoulder 24. As the flange 32 is stopped by the shoulder 24, the swabbing tool may be readily pulled upwardly and easily disengaged irom the threaded bore 28. As hereinbefore set forth, the seal member 14 is constructed from flexible material, thus, the swabbing tool may be easily pulled from the threaded engagement with the bore 23.

The interior of the tubing string is normally filled with well fluid. It will be apparent that the downward movement of the seal member 14 therein will force the well fluid downwardly in the tubing. Thus, as the seal member 14 is disposed within the enlarged portion 22, the well fluid exerts an upward pressure on the lower end 36 thereof for retaining the seal member 14 in an uppermost position, as shown in the drawing. The upward force of the well fluid will urge the flange 32 into a tight sealing engagement with the shoulder 24 for precluding any leakage of fluid therearound. Siimlarly, the upward force of the fluid will tend to flex the lower flange 34 radially outward into a sealing contact with the enlarged portion 22 for assisting in precluding the leakage of the well fluid therearound.

When the tubing string has been pulled from the well, the dual completion packer unit 19 may be readily removed from the enlarged portion 22. The tubing string may be re-inserted or disposed within the well bore after the servicing operation has been completed. It is preferable to leave the housing 12 interposed within the tubing string in order to provide for a sealing thereof at any future time when servicing is necessary.

From the foregoing, it will be apparent that the present invention provides a novel plugging apparatus for an oil well string whereby the flow of fluid through the well tubing may be efficiently stopped for permitting a pulling of the tubing string from the well bore. Thus, the well fluid will not flow upwardly through the tubing during the pulling operation. The hazards from the upwardly flowing well fluid are thereby eliminated to provide a more pleasant and less hazardous working area for the servic ing personnel. Furthermore, there is no necessity for killing the well prior to the pulling of the tubing, thereby eliminating the disadvantages thereof. The novel plugging apparatus is simple and efficient in operation and economical and durable in construction.

Changes may be made in the combination and arrange 15 2,595,715

4 ment of parts as heretofore set forth in the specification and shown in the drawing, it being understood that any modification in the precise embodiment of the invention may be made within the scope of the following claims without departing from the spirit of the invention.

I claim:

1. A plugging apparatus for a well tubing string having a dual completion packer unit provided therein, and comprising a tubular housing adapted to be interposed be tween the tubing string and the packerunit, a cylindrical sealing member adapted for longitudinal movement within the housing, said sealing member provided with an axially extending threaded bore for facilitating the longitudinal movement thereof in one direction, an enlarged bore portion provided in the housing for receiving the sealing member upon a downward movement thereof within the housing, shoulder means provided adjacent the enlarged bore portion for precluding upward movement of the sealing member, said packer unit precluding downward movement of the sealing member from the enlarged portion, and a pair of spaced circumferential flange members provided on the sealing member for engaging the walls of the enlarged bore portion to preclude leakage of fluid therebetween.

2. A plugging apparatus for a well tubing string having a dual completion packer unit provided therein, and comprising a tubular housing adapted to be interposed between the tubing string and the packer unit, a cylindrical sealing member adapted for longitudinal movement downwardly within the housing member, said sealing member provided with means for facilitating the longitudinal movement thereof, an enlarged bore portion provided within the housing for receiving the sealing member upon a downward movement thereof within the housing, shoulder means provided on the inner periphery of the housing for retaining the sealing member within the eniarged bore portion, a tapered surface provided on the inner periphery of the housing adjacent a shoulder means for facilitating disposition of the sealing member within the enlarged bore portion, and a pair of spaced flange members provided on the outer periphery of the sealing member for contacting the inner periphery of the enlarged bore portion of the housing for precluding the leakage of fluid therearound.

3. A plugging apparatus for a well tubing string having a dual completion packer unit providedtherein, and comprising a tubular housing adapted to be interposed between the tubing string and the packer-unit, a cylindrical sealing member adapted for longitudinal movement within the housing, said sealing member provided with means for facilitating the longitudinal movement thereof in one direction, an'enlarged bore portion provided in the housing for receiving the sealing member upon a downward movement thereof within the housing, shoulder means provided adjacent the enlarged bore portion for precluding upward movement of the sealing member, said packer unit precluding downward movement of the sealing member from the enlarged portion, and a pair of spaced circumferential flange members provided on the sealing member for engaging the walls of the enlarged bore portion to preclude leakage of fluid therebetween.

References Cited in the file of this patent UNITED STATES PATENTS 1,209,805 1306 Dec. 26, 1916 1,299,487 Loeben Apr. 8 l9l9 2,029,380 Manning Feb. 4, 1936 2,095,899 Yancey Oct. 12, 1937 2,128,352 Creighton Aug. 30, 1938 2,169,568 Morrisett Aug. 15, 1939 2,368,431 Smith Jan. 30, 1945 2,481,422. Haynes et al Sept. 6, 1949 2,559,536 Haynes et a1 July 3, 1951 Sloan May 6, 1952 

